Cross-Calibration and Thermal Analysis with SDO/AIA

The measured intensity in each pixel of the images from SDO/AIA and similar narrowband EUV imagers can be used to perform quantitative analysis of the temperature and density of the plasma along the line of sight. This type of analysis depends very sensitively on the accuracy of the instrument calibration and the atomic physics models used to estimate the plasma emissivity. Unfortunately, it is difficult to assess the accuracy of these parameters, other than by verifying the consistency of datasets from different instruments and analysis techniques. Here we use differential emission measure models of the plasma temperature structure constrained by spectroscopic observations from SDO/EVE and Hinode/EIS to assess the AIA temperature response functions. The response functions generated using the CHIANTI database underestimate the emission from the non-flaring corona in the 94 and 131 Å channels. We find empirical corrections to the temperature response functions for these channels that are internally consistent and provide good agreement with DEMs obtained from other instruments. We present an assessment of the reliability of thermal analysis using AIA data based on the current state of the instrument calibration and spectral models.